In general, various interactive display and computer display systems are known in the art. The following are examples of such systems.
The article entitled "Absolute Display Window Mouse/Mice", Research Disclosure, March 1987, No. 275, by Feigenblatt discloses flat panel displays which are manually-movable on a large image surface and which serve as a panning display window. The position and orientation of the displays on the large image surface are sensed by digitizers, and this information is used to formulate image information to be shown on the displays. The article discloses that a variety of conventional locating devices, such as sound sensors, may be employed to sense the display position/orientation.
U.S. Pat. No. 4,730,186 to Koga et al discloses several computer display systems, each of which includes an integrated input/output device which incorporates a pen-to-wire grid electromagnetically-coupled digitizer and a flat-panel Liquid Crystal Display (LCD). One display system includes a relatively large cathode ray tube (CRT) display, and a relatively small LCD for the pen-digitizer. In order to store pixel data for the CRT, the computer display system includes a frame memory. The contents of the frame memory for the CRT may be copied to the display of the pen-digitizer. The display system also includes a scrolling and a zooming function.
In order to provide the scrolling and zooming functions, the pen-digitizer input has three coordinate-input areas. Each of these coordinate-input areas is substantially rectangular in shape and is specified in terms of X and Y coordinate values entered by the pen-digitizer. If a pair of coordinates values (X,Y) from the pen-digitizer is within the scroll appointment area, then a coordinate transformation is performed by the computer to normalize the coordinate values to a pair of start-address coordinates (X.sub.0, Y.sub.0), and then the computer transfers the start-address coordinates to a CRT/LCD coordinate transformation controller.
For the zooming function, if the pair of coordinates (X,Y) from the pen-digitizer is within the zooming control section area, a display mode is toggled between a one-half display mode and a normal display mode. In the one-half zooming display mode, every other pixel in the X and Y directions is omitted from the data to be displayed.
U.S. Pat. No. 4,451,895 to Sliwkowski discloses an interactive computer-aided design system which includes two CRT screens: a graphic screen for viewing the end product of a graphic design, and a function screen for entering data. Data may be entered into the computer-aided design system by a light pen interacting with the function screen.
U.S. Pat. No. 4,562,433 to Biferno discloses a display system which includes two displays: a primary LCD and a backup display. The backup display is located behind the primary display relative to the line of sight of a viewer. The primary LCD becomes transparent upon failure in which case the backup display becomes visible to the viewer.
U.S. Pat. No. 4,641,255 to Hohmann discloses a tank or other military-device simulator which displays a computer-synthesized image of a battle situation on a television monitor placed in the field of view of an aiming periscope for viewing by a gunner trainee operating the simulator. A monitor buffer memory, a target memory and a sight memory are provided in a monitor control unit for storing image data for a background-image, target-image and reticle-image components of the computer-synthesized image, respectively. The background-image component of the computer-synthesized image is a "cut-out" portion taken from a larger background image. The background image is selected by signals from control handles in the simulator. The control handles allow a trainee to follow the reticle of a movable target while the cut-out from the background image experiences a continous change.
U.S. Pat. No. 4,734,690 to Waller discloses a graphic display terminal for storing and displaying three-dimensional graphic information. The graphic display terminal permits a user to view the stored three-dimensional graphic information from different directions. The terminal includes a spherical panning system which enables the user to pan around a displayed object so as to view the object from different directions. The user can enter changes in longitude and latitude to permit a new viewing point. The graphic display terminal also includes a zoom feature so that the display can be magnified.